Alkyl keto-alkyl sulfites and their uses

ABSTRACT

SULFITE ESTERS OF THE FOLLOWING GENERAL FORMULA ARE USED AS CHEMICAL PRUNING AGENTS:   R-O-SO-O-R&#39;&#39;   WHEREIN R IS AN ALKYL OR A HALOALKYL RADICAL HAVING FROM 1 TO 18 CARBON ATOMS AND R&#39;&#39; IS A KETOALKYL GROUP HAVING 3 TO 10 CARBON ATOMS AND THEIR HALO-SUBSTITUTED DERIVATIVES.

United States Patent Office 3,707,363 Patented Dec. 26, 1972 3,707,363ALKYL KETO-ALKYL SULFITES AN D THEIR USES Rupert A. Covey, Wolcott, andBogislav von Schmeling and Charles E. Crittendon, Hamden, Conn.,assignors to Uniroyal, Inc., New York, N.Y. No Drawing. Originalapplication Dec. 22, 1967, Ser. No. 692,714, now Patent No. 3,564,038,dated Feb. 16, 1971. Divided and this application May 1, 1970, Ser.

Int. Cl. A01n 9/14 U.S. Cl. 71-78 8 Claims ABSTRACT OF THE DISCLOSURESulfite esters of the following general formula are used as chemicalpruning agents:

Ros '-o-R' wherein R is an alkyl or a haloalkyl radical having from 1 to18 carbon atoms and R is a ketoalkyl group having 3 to 10 carbon atomsand their halo-substituted derivatives.

This is a division of application Ser. No. 692,714, filed Dec. 22, 1967now U.S. Pat. 3,564,038.

This invention relates to alkyl ketoalkyl sulfites as new compositionsand their biological uses.

The compounds of the invention have the formula:

in which R is an alkyl or a haloalkyl radical of up to 18 carbon atomsand R is a ketoalkyl radical of 3 to 10 carbon atoms and theirhalo-substituted derivatives.

Examples of R are methyl, ethyl, propyl, isopropyl, butyl, isobutyl,sec.-butyl, tert.-butyl, amyl, hexyl, 2-ethylhexyl, heptyl, octyl,nonyl, decyl, isodecyl, undecyl, dodecyl, hexadecyl, octadecyl,chlorooctyl and bromodecyl.

Examples of R are 2-ketopropyl, 3-ketobutyl, 2-ketopentyl, 3-ketopentyl,4-ketopentyl, 2-methyl-3-ketobutyl, 3-keto-2-butyl, 4-ketohexyl,3-ketoheptyl, 7-ketooctyl, 3- ethyl-4-ketohexyl, 4-keto-3-decyl,3-keto-4-chl0ropentyl, and 2-bromo-4-keto-hexyl.

The chemicals of the invention may be prepared by reacting a ketoalkanolwith the chlorosulfinate of an alcohol; the latter may be made byreacting the alcohol with thionyl chloride. Such preparation isillustrated by the following reactions:

ROH S0011 R-OSCl HCl The first reaction is carried out at a temperatureof betwen C. and 30 C., preferably near 0 C., and the yield ofchlorosulfinate is nearly quantitative. An inert solvent such asbenzene, xylene or solvent naphtha may be used, but is generallyunnecesary. The second reaction is carried out in the presence of an HClacceptor, such as pyridine, dimethylaniline or trimethylamine, and in asolvent such as benzene, xylene, or solvent naphtha. The reactiontemperature is generally between 10 C. and 50 C., and preferably near 0C.

The following is an example which illustrates the preparation of thecompounds of the present invention:

EXAMPLE I Preparation of 2-ketopropyl octyl sulfite To 910 g. (7.0moles) n-octyl alcohol cooled to 5-10 was added dropwise with stirring635 ml. (1040 g., 8.75 moles) thionyl chloride, keeping a maximumreaction temperature of 25. The mixture was allowed to stand 16 hoursand then the dissolved HCl was removed with an aspirator. Furtherstripping of the chlorosulfinate was carried out at 25 (3 mm.) by meansof a vacuum pump. The yield is nearly quantitative and the material isof sufficient quality to be reacted directly in the'next step.

To a cooled solution of 10.6 g. (0.05 mole) n-octyl chlorosulfinate in20 ml. benzene was added a solution of 3.7 g. (0.05 mole) hydroxyacetoneand a 4.0 ml. (4.0 g., 0.05 mole) pyridine in 5 ml. benzene, keeping thereaction temperature below 10. The mixture was stirred for a few minutesand then was washed with 25 ml. water, 25 ml. 2 N NaOH and twice with 25ml. saturated salt solution. The organic layer was dried and the solventwas removed under reduced pressure. The product was distilled as a paleyellow oil: B.EP., 113-119 (0.5 mm.); yield, 7.3 g. (58% Analysis.-Calcdfor C H O' S (percent): S, 12.81. Found: S, 12.39.

Sulfur analyses and boiling points of other chemicals of the presentinvention are shown in Table I.

In accordance with this invention it has been discovered that alkylketoalkyl sulfides have outstanding chemical activity with regard tokilling meristematic buds. They may be used for killing meristematicbuds on ornamental and agricultural herbaceous, semi-woody and woodyplants such as chrysanthemum, cotton, azalea, apple and tobacco.Meristematic buds include both terminal and auxiliary buds. Theselective killing of terminal buds is an application for which thechemicals of the invention are particularly useful.

Additionally, the compounds of the invention are useful as insecticidesand nematocides.

For the several biological uses, the compounds of the present inventionmay be applied to plants, which term includes various plant parts suchas seeds, flowers, fruits, vegetables, roots and foliage in variousmanners. Seeds may be treated directly with the chemical beforeplanting, or seeds may be treated with the chemical by incorporating thechemical in the soil before or after planting the seeds. The chemicalsmay be applied to plants in an inert medium as a dust in admixture witha powdered solid carrier, such as the various mineral silicates, e.g.,mica, talc, pyrophyllite and clays or as an aqueous composition. Thechemicals may be applied in admixture with small amounts ofsurface-active wetting agents, which may be anionic, non-ionic, orcationic surface-active agents, generally as aqueous compositions. Thechemicals may be dissolved in organic solvents such as acetone, benzene,or kerosene, and the solutions of the chemicals emulsified in water withthe aid of surface-active agents. Such surface-active agents are wellknown and reference is made to U.S. Pat. No. 2,547,724, columns 3 and 4,for detailed examples of the same. The chemicals of the invention may beadmixed with powdered solid carriers, such as mineral silicates,together with a surface-active agent so that a wettable powder may beobtained which may be applied directly to plants, or which may be shakenup with water for application to the plants in that form.

The concentration of active chemical in the useful chemical pruningformulations may vary widely, e.g., from 1% to 95%. Generally, theactive chemical in dispersions which are applied are from 0.05% to 6.0%.The amount per acre of active chemical applied may vary from 0.5 poundto 50 pounds depending on the plant being treated and other factorsknown to those skilled in the art.

Where the compounds are used as insecticides the concentration of activeingredient in the formulation ranges from 1 to 95 Generally, thedispersion which is applied has from 0.001 to 85% active chemical. Theapplication rate is 0.1 to 25 lbs. per acre of active chemical.

For nematicide application, formulations generally contain 0.001 to 90%of active chemical and the dispersions which are applied have from 0.001to 4.0%. Here the application rate ranges from 0.1 to 25 lbs/acre.

The following example illustrates the use of the compounds of theinvention for killing meristematic buds:

EXAMPLE II Rooted cuttings of Chrysanthemum morifolium cv. ImprovedIndianapolis Yellow are planted in 12 oz. styrofoam pots in a sterilizedsoil mixture of one part soil, one part peat moss, and one parthorticultural perlite. At planting and weekly thereafter, the plants arefertilized with 25-5-30 analysis fertilizer at the rate of one ounce perthree gallons of water. For seven to ten days following planting, theplants are placed under a polyethylene "tent and frequently syringed toprovide conditions of both high temperature and high relative humidity,respectively. The potted plants are maintained under longday conditionsby the use of supplemental fluoroescent light from five pm. to nine p.m.and from five a.m. to seven a.m. daily. Ten days to two weeks afterplanting the established plants are ready to treat.

Two and one-half grams of the selected compound and 0.23 gram ofisooctyl phenyl polyethoxy ethanol are combined to produce anemulsifiable concentrate, 90% of which is the active ingredient. Enoughwater is added to the 2.83 grams of emulsifiable concentrate to bringthe total volume to 100 ml. This results in a 25,000 p.p.m. solution.Dilutions to 10,000, 4,000 and 2,000 p.p.m. are prepared by diluting theappropriate amount of the 25,000 p.p.m. solution with water to whichisooctyl phenyl polyethoxy ethanol has been added at the rate of twodrops per 100 ml.

The aqueous formulations are applied as a foliar spray until the plantsare wet to run-off. The plants are allowed to dry and then placed in thegreenhouse at a temperature of 65 F. minimum night temperature.

With 12 to 24 hours following the application of optimum dosages andformulations of said compounds, the shoot apex, embryonic leaves andembryonic axillary meristems (hereinafter collectively referred to asthe terminal meristem) turn black and are very flacaid. Within the nextfew days this same dead tissue turns grayish and a constricution appearson the stem at the proximal limit of the killed tissue. At optimumconcentrations the compounds are non-phytotoxic to matured axillarymeristems, leaves, and stem tissue. This process of killing the terminalmeristem with aqueous emulsions of the compounds of the mentioned typeis referred to as chemical prung At concentrations in excess of optimumboth the terminal and axillary meristems may be killed without causingdamage to foliage and stem tissue With other compounds, concentrationsin excess of optimum may kill the terminal meristem and be phytotoxic tomature leaves but may not kill the axillary meristems. Concentrations inexcess of optimum of still other com- TAB LE II Minimum pruningPhytodosages toxicity Compound p.m.) rating Z-ketopropyl hexyl sulfite7, 000 Trace. 2-ketopropyl n-octyl sulfite 4, 000 Do. 2-ketopropyl2ccty1 sulfite- 5, 000 D0. 2-ketopropyl decyl su1fite-. 5, 000 Do.4-ketopentyl octyl sulfite. 25, 000 Slight. 2-methyl-3-ketobutyl octylsulfi -20, 000 Moderate. 3-keto-2-butyl octyl sulfite. 9, 00 Traci-1.3-ketobutyl oetyl sulfite -20, 000 Slight.

l Axillary meristems killed.

The activity of the chemicals of the present invention as insecticidesis shown against mosquito larvae and spider mites in the followingexample:

EXAMPLE III In the mosquito larvae test, 10 mg. of chemical is dissolvedin 1 ml. of acetone and diluted to ml. with tap water to give a 100p.p.m. solution. Dilution to 10 p.p.m. is made with tap water. Twentyfive ml. aliquots of each dosage, replicated once, are placed in testtubes and ten 4th instar larvae of Aedes aegypti are added and the tubesare held at 70 F. in darkness for 72 hours. At the end of this periodthe live and dead are counted and percent control calculated.

In the mite contact test, 400 mg. of chemical is dissolved in 10 ml. ofacetone and two drops of Triton X--100. This is then diluted to 200 ml.with distilled water to give a concentration of 2000 p.p.m.Four-week-old cotton seedlings, grown in 12 oz. styrofoam cups, are usedas the host plants. A quarter sized circle of tanglefoot is placed onboth primary leaves of each cotton plant in order to confine the mitesto the upper leaf surface. Approximately 24 hours prior to spraying withsaid chemical, about ten two-spotted spider mites, Tetranvchus urticae,are placed inside each circle. Plants are sprayed to run-ofi with the2000 p.p.m. solution using a concentrate sprayer which is positioned 6"to 12" from the plants. One plant (two leaves) is used in each pot forone replicate. Two replicates are used for each chemical tested. Initialcounts of the mites present are made short- ]y after spraying. Theplants are held five days in the greenhouse, at which time a final countis made of the live adult mites remaining on the leaves. The percentcontrol is calculated by using Abbotts formula:

Percent control= Percent mites living (untreated) Percent mites living(treated) X100 Percent mites living (untreated) 1 Igooctyl phenylpolyethoxy ethanol surface active wetting agen Table III shows theinsecticidal activity of the alkyl ketoalkyl sulfites:

The nematocidal activity of the compounds of the invention is shown inthe following example:

EXAMPLE IV Three hundred milligrams chemical is dissolved in ml. ofacetone. Ninety milligrams (three drops from a standard medicinedropper) of this 3.0% solution is added to a BPI standard watch glasscontaining 150 mg. of a 0.01% solution of Triton X-100 (five drops) indistilled water. Thirty milligrams (1 drop) of a nematode suspensioncontaining 50-100 live Panagrellus redivivus nematodes is added to thewatch glass containing the chemical preparation. The final concentrationof chemical in the BPI watch glass is 1.0% (10,000 p.p.m.). The test isconducted in duplicate using a dilution series. An untreated check,i.e., two watch glasses containing 0.01% Triton X-100 solution andnematodes but no chemical, is included in the test. The watch glassesare placed in 100 x mm. inverted Petri plates and scaled with water toavoid evaporation. The test is kept in the laboratory at roomtemperature. The results are taken by microscopic inspection of thenematodes in the watch glasses. They are recorded as percent nematodecontrol by contact after 48 hours.

Table IV shows the nematocidal activity of several alkyl ketoalkylsulfites.

TABLE IV Percent control as a contact nematocide with- Having thusdescribed our invention, what we claim and desire to protect by LettersPatent is:

1. A method of killing meristematic buds on ornamental and agriculturalherbaceous, semi-woody and woody plants comprising applying to the buds,in an amount sufiicient to kill them, a compound having the formula:

2. The method of claim Z-ketopropyl hexyl sulfite.

3. The method of claim Z-ketopropyl n-octyl sulfite.

4. The method of claim 2-ketopropyl 2-octyl sulfite.

5. The method of claim 4-ketopenty1 octyl sulfite.

6. The method of claim 1 wherein 2-methyl-3-ketobutyl octyl sulfite.

7. The method of claim 1 wherein 3-keto-2-butyl octyl sulfite.

8. The method of claim 1 wherein 3-ketobutyl octyl sulfite.

1 wherein the compound 1 wherein the compound 1 wherein the compound 1wherein the compound the compound the compound the compound ReferencesCited UNITED STATES PATENTS 2,802,727 8/1957 Harris 7l103 3,179,6874/1965 Covey et al. 7l103 3,006,751 10/1961 Brugmann, Jr. et al. 7l782,746,853 5/1956 Yowell et al. 7l78 LEWIS GOTTS, Primary Examiner G.HOLLRAH, Assistant Examiner U.S. Cl. X.-R. 71-76 December 26, 1972ROBERT GOTTSCHALK Commissioner of Patents Dated Rupert A. Covey, efl:a1.

Signed and sealed this 29th day of May 1973;

It is certified that error appears in the above-identified patent andthat said Letters Patent are hereby corrected as shown below:

Patent No.

Inventor(s) 001mm 6, lines 9-10, claim 1, after the structural formulainsert "wherein R is an alkyl or a monohalo'alkyl group having 1 to 10carbon atoms and R is a ketoalkyl group having 3 to 5 carbon atoms or amonohalosubsti'buted derivative thereof,

(SEAL) Attes't:

EDWARD M.FLETCHER,JR. Attesting Officer

